1. Field of the Invention
This invention relates to a manifold for hydronic systems and, more particularly, a manifold for hot water heating systems.
2. Discussion of the Related Art
A hydronic system involves the transfer of heat, for either heating or cooling applications, by a circulating fluid, such as water or vapor, in a closed system of pipes. A forced hot water heating system, which is a type of hydronic system commonly installed in residential houses, circulates water through a network of pipes to carry heat from a boiler to remotely located radiators which transfer heat to the surrounding air to heat the house.
Multiple zone heating systems, which comprise several individually controlled heating loops or circuits, are now routinely installed in residential houses. A multi-zone heating system allows the occupant of the house to maintain different temperatures in separate zones or areas of the house, such as particular rooms or separate floor levels, to reduce energy costs by selectively raising and lowering the temperature in the separate areas. A multi-zone heating system can also maintain a more uniform temperature throughout the house by providing heat to the cooler zones without also heating the warmer zones.
Although several benefits are derived from a multi-zone heating system, a significant amount of labor is involved in connecting the piping for the separate zones to the inlet and the outlet of the boiler. Since a conventional boiler includes a single inlet and a single outlet, the piping for each zone is typically coupled to the boiler in a complex arrangement of pipes and fittings that involves many joints that must be properly sealed to avoid system leaks. As the number of heating zones increases, so does the number of fittings and joints which increase the amount of labor and material costs and the chance of leaks associated with installing the system.
A hydronic manifold, as shown in FIG. 1, was developed by Applicants for use in multi-zone hot water heating systems to eliminate fittings and joints associated with conventional installations and thereby reduce installation costs and potential leaks. The manifold 10 is a welded construction and includes a plurality of branch conduits 12, extending from a header conduit 14, for coupling the separate heating zones of the system to the boiler. The manifold can be used as a supply header and a return header. While generally reducing the costs and the chance of leaks associated with the installation of heating systems, there is still a need for a further reduction in costs and leaks.
A hot water heating system also incorporates several separately installed components for proper system operation. For example, a separate air scoop and vent arrangement is installed on the supply or outlet side of the boiler to purge entrapped air from the water before it is circulated through the heating system. As heated water flows through the air scoop, suspended air bubbles are directed from the water stream to the air vent to be purged from the system. The heating system also includes an expansion tank to accommodate the thermal expansion of the heated water. The expansion tank is also typically coupled to the system piping on the supply side of the boiler using a separate fitting or a connection provided on the air scoop. Installation of these components also involves significant material and labor costs.
In view of the foregoing, it is an object of the present invention to provide an improved hydronic manifold for installing a heating system.